Background Phase 2 of the Norwich Testing Initiative (NTI2) was a SARS-CoV-2 PCR testing programme at the University of East Anglia, which ran from September to December 2020. It aimed to identify asymptomatic COVID-19 infections and limit outbreaks on campus. The NTI2 evaluation explored testing uptake, positivity rates, isolation compliance and the links between viral load and symptoms.

Methods All staff and students (21,762) were eligible for testing. Users registered for the programme using a web application, which collected personal, demographic and location data. Users collected tests from a central location on campus, self-administered a nasopharyngeal swab and returned tests to a drop-off point. PCR testing was conducted by two laboratories. All those with a positive result were contacted by telephone for self-isolation advice and support. At this point symptom, isolation and location data were collected. The programme used a broader definition of COVID-19 symptoms than that used by NHS Test and Trace. Data were encrypted and stored in a data warehouse. Microsoft Excel was used to collate, clean and analyse the data.

Results 188 of 6537 (2.9%) users tested positive for COVID-19. The majority (82%) were students aged 18–24 years. Positivity rates were highest in students (3.5%), those living on campus (6.5%) and BAME groups (4%). There was clustering of cases in university halls: positivity rates in halls varied between 0% and 31%, with 18% of halls containing over half the cases on campus. Positivity rates spiked near the beginning of the programme and then declined over the course of the term. 99/187 (53%) cases reported symptoms of COVID-19. 37/99 (35%) symptomatic cases were not isolating. There was no significant relationship between PCR C_t values and self-reported symptoms.

Conclusion NTI2 may have contributed to a decline in cases of COVID-19 during the testing period, as the incidence of COVID-19 in the local area increased during this period. Transmission within halls of residence may have contributed to high positivity rates on campus. A high proportion of users reported symptoms of COVID-19 infection, despite this being an asymptomatic testing programme. Over a third of symptomatic cases were not isolating prior to receiving their result . These findings suggest that testing and isolating messaging may not be reaching the student population. Those with symptoms had a similar viral load to those without and may be similarly infectious.